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Solve the equation `64.9^(x)-84(12^(x))+27(16^(x))=0` |
Answer» Here `9xx16=(12)^(2)` Then, we divide its bothsides by`12^(x)` and obtain `implies64.(3/4)^(x)-84+27.(4/3)^(x)=0`…..i Let `(3/4)^(x)=t`, the eq. (i) reduce in te form `64t^(2)-84t+27=0` `:.t_(1)=3/4` and `t_(2)=9/16` then`(3/4)^(x)=(3/4)^(1)` and `(3/4)^(x)=(3/4)^(2)` `:.x_(1)=1` and `x_(2)=2` Hence, roots of the original equation are `x_(1)=1` and `x_(2)=2` |
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